For example, Patent Document 1 discloses a technique that is related to the present invention and relates to a flow rate controller of an internal combustion engine for adjusting at least one of a flow rate of exhaust gas that is recirculated to an intake system from an exhaust system of the internal combustion engine via an exhaust gas recirculation (EGR) passage and a flow rate of fresh air that flows into the internal combustion engine. Patent Document 1 discloses a controller of a diesel engine that fully closes an intake throttle valve in a fuel cut state of the engine and fully opens an EGR valve. Thus, fresh air flows as is into an exhaust passage in the fuel cut state. Consequently, the controller is adapted to suppress a reduction in a temperature of exhaust gas purifying means, thereby maintaining exhaust gas purification performance.